Imaging apparatus, data recording method and data-display control method, and computer program

ABSTRACT

An imaging apparatus includes an imaging unit configured to execute processing to capture an image; a GPS (Global Positioning System) device configured to execute position calculation processing based on data received from a satellite; a power-supply control unit configured to control power supply to the GPS device; an apparatus control unit configured to monitor a state of photographing by a user to calculate a frequency of use of the imaging unit per unit time, and to cause the power-supply control unit to intermittently supply power to the GPS device when the calculated use frequency is lower than a predetermined threshold; and a data-recording control unit configured to generate photographed data attribute information in which positional information acquired in the GPS device is set as attribute information of an acquired image in the imaging unit, and to execute processing to store the photographed data attribute information in a storing unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from Japanese Patent ApplicationNo. JP 2005-353011 filed on Dec. 7, 2005, the disclosure of which ishereby incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an imaging apparatus, a data recordingmethod and a data-display control method, and a computer program. Moreparticularly, the present invention relates to an imaging apparatus thatincludes a camera provided with a GPS (Global Positioning System),acquires positional information corresponding to photographed data, andexecutes various kinds of data processing using the acquiredinformation, a data recording method and a data-display control methodin the imaging apparatus, and a computer program for causing a computerto execute processing in the imaging apparatus.

2. Description of the Related Art

In recent years, an imaging apparatus such as a video camera or a stillcamera that is given a GPS (Global Positioning System) function to makeit possible to acquire positional information has been proposed andused.

By mounting a GPS device in the imaging apparatus in this way, forexample, it is possible to perform processing for, for example,calculating positional information corresponding to a photographedimage, calculating a moving locus of a user (a photographer), andpresenting the moving locus on a display of a personal computer (PC) orthe like to which the camera is connected.

To represent a movement history using the positional information, amethod of typically positioning a present location with the GPS device,recording a log including acquired positional information in a memory,and rendering a moving locus on the basis of the log is generally used.This is a method of verifying, with a time stamp serving as timeinformation set in periodically acquired GPS information as a key,correspondence of photographing date and time information correspondingto photographed contents and associating the photographed data and GPSpositional information to acquire a moving locus.

However, in this method, it is necessary to typically supply electricityto the GPS device and continuously execute information reception from asatellite to continuously record logs. As a result, power consumption inthe GPS device increases. In portable apparatuses such as a video cameraand a still camera generally driven by batteries, the batteriesundesirably run down earlier than usual.

In order to present a moving locus or the like to the user, it is ageneral practice to connect the camera to the PC and perform processingfor outputting log information and photographed data acquired by the GPSdevice to the PC and executing data processing for locus presentationprocessing on the basis of the log information and the photographed datausing an application on the PC to present a moving locus on the displayof the PC. In other words, processing for instantaneously orconveniently combining the moving locus with a map or the like anddisplaying the moving locus on a liquid crystal screen or the like of aphotographing apparatus body has not been realized.

This is because log data including positional information and timeinformation acquired by the GPS device is recorded in a memory asindependent log data and, on the other hand, the photographed data isindependently recorded in a separate file together with attributeinformation such as photographing date and time information. The logdata and the photographed data are held in the memories as separaterecording data. Thus, in performing the processing, the presentation oflocus information, and the like described above, it is necessary toperform processing for searching for, with a time stamp serving as timeinformation set in GPS information as a key, correspondence ofphotographing date and time information corresponding to photographedcontents and processing for associating the photographed data with GPSpositional information to calculate a moving locus. When these kinds ofprocessing are executed in the inside of the imaging apparatus,processing loads are excessively large. Thus, in general, the data isoutputted to the PC or the like to perform the processing.

In a system in which information acquired by a GPS device andphotographed data related information are separately recorded andmanaged, when it is attempted to perform processing for displaying animaginary moving locus among photographed contents as a user feelsconvenient, for example, processing for displaying a positional relationamong photographed contents in plural times of travels to France indifferent periods on one screen in a compound state, complicatedprocessing has to be executed.

A procedure of the processing is as follows. First, plural image datafiles, in which photographed images of the plural times of travels toFrance are stored, are selected. Association of image data in the imagedata files including photographed data generated in these differentperiods with GPS information logs is executed. Thereafter, GPSinformation associated with the image data of the plural different imagedata files is rearranged to generate display data. In this way, theprocessing is complicated and heavy-load processing including pluralprocessing processes. As a result, it takes time until data isdisplayed, it is difficult to perform the processing in the imagingapparatus, and processing in the PC is necessary.

SUMMARY OF THE INVENTION

Therefore, it is desirable to provide an imaging apparatus such as avideo camera or a still camera mounted with a GPS module, the imagingapparatus controlling power supply to the GPS module to reduce powerconsumption and recording positional information, time information, andthe like acquired by the GPS device in direct association withphotographed image data to efficiently and promptly acquire positionalinformation corresponding to the image data and realize various dataprocessing and information display based on the photographed images andthe positional information, such as presentation of moving locusinformation of a user, a data recording method and a data-displaycontrol method in the imaging apparatus, and a computer program forcausing a computer to execute processing in the imaging apparatus.

According to an embodiment of the invention, there is provided animaging apparatus including an imaging unit configured to executeprocessing to capture an image; a GPS (Global Positioning System) deviceconfigured to execute position calculation processing based on datareceived from a satellite; a power-supply control unit configured tocontrol power supply to the GPS device; an apparatus control unitconfigured to monitor a state of photographing by a user to calculate afrequency of use of the imaging unit per unit time, and to cause thepower-supply control unit to intermittently supply power to the GPSdevice when the calculated use frequency is lower than a predeterminedthreshold; and a data-recording control unit configured to generatephotographed data attribute information in which positional informationacquired in the GPS device is set as attribute information of anacquired image in the imaging unit, and to execute processing to storethe photographed data attribute information in a storing unit.

Preferably, the data-recording control unit is configured to executeprocessing to record latitude and longitude information and timeinformation acquired in the GPS device in the storing unit as thephotographed data attribute information.

Preferably, the imaging apparatus further includes a data-displaycontrol unit configured to read the photographed data attributeinformation stored in the storing unit and to generate displayinformation indicating a photographing position on a map based onpositional information corresponding to image data included in thephotographed data attribute information.

Preferably, the data-display control unit is configured to generatedisplay information indicating a moving locus of the user based onphotographing time information corresponding to the image data includedin the photographed data attribute information.

Preferably, the data-display control unit is configured to read pluralpieces of photographed data attribute information corresponding toplural different photographed image data files, to merge the pluralpieces of photographed data attribute information, and to generatedisplay information in which photographing positions of images includedin the plural different photographed image data files are displayed on amap.

Preferably, the apparatus control unit is configured to calculate aphotographing frequency in the imaging apparatus and to cause thepower-supply control unit to intermittently supply power to the GPSdevice and when the calculated photographing frequency is lower than apreset threshold, and to cause the power-supply control unit to supplycontinuous power to the GPS device when the calculated photographingfrequency is equal to or greater than the preset threshold.

According to another embodiment of the invention, there is provided adata recording method in an imaging apparatus, the method includingcapturing an image; monitoring a state of photographing by a user tocalculate a frequency of use of the imaging apparatus per unit time;controlling power supplied to a GPS (Global Positioning System) deviceconfigured to execute position calculation processing based on datareceived from a satellite so that power is intermittently supplied tothe GPS device when the calculated use frequency is lower than apredetermined threshold; performing positioning by the GPS device; andgenerating photographed data attribute information in which positionalinformation acquired in the GPS device is set as attribute informationof the captured image and storing the photographed data attributeinformation in a storing unit.

Preferably, the generating and storing steps include recording latitudeand longitude information and time information acquired in the GPSdevice in the storing unit as the photographed data attributeinformation.

According to still another embodiment of the invention, there isprovided a data-display control method for image data in an imagingapparatus, the method including reading photographed data attributeinformation stored in a storing unit and acquiring positionalinformation corresponding to image data included in the photographeddata attribute information; acquiring map information of a positioncorresponding to the positional information from a map database based onthe positional information corresponding to the image data; andgenerating display information in which identification informationindicating the position corresponding to the image data is set on a mapacquired from the map database and outputting the display information toa display unit.

Preferably, the data-display control method further includes generatingdisplay information indicating a moving locus of a user based onphotographing time information corresponding to the image data includedin the photographed data attribute information.

Preferably, the data-display control method further includes readingplural pieces of photographed data attribute information correspondingto plural different photographed image data files, merging the pluralpieces of photographed data attribute information, and generatingdisplay information in which photographing positions of images includedin the plural different photographed image data files are displayed on amap.

According to still another embodiment of the invention, there isprovided a computer program that causes a computer to execute a datarecording method in an imaging apparatus, the method including capturingan image; monitoring a state of photographing by a user to calculate afrequency of use of the imaging apparatus per unit time; controllingpower supplied to a GPS (Global Positioning System) device configured toexecute position calculation processing based on data received from asatellite so that power is intermittently supplied to the GPS devicewhen the calculated use frequency is lower than a predeterminedthreshold; performing positioning by the GPS device; and generatingphotographed data attribute information in which positional informationacquired in the GPS device is set as attribute information of thecaptured image and storing the photographed data attribute informationin a storing unit.

According to still another embodiment of the invention, there isprovided a computer program that causes a computer to execute adata-display control method for image data in an imaging apparatus, themethod including reading photographed data attribute information storedin a storing unit and acquiring positional information corresponding toimage data included in the photographed data attribute information;acquiring map information of a position corresponding to the positionalinformation from a map database based on positional informationcorresponding to the image data; and generating display information inwhich identification information indicating the position correspondingto the image data is set on a map acquired from the map database andoutputting the display information to a display unit.

The computer programs according to the embodiments are computer programsprovided in a computer readable format that can be provided to, forexample, a general-purpose computer system capable of executing variousprogram codes using a storage medium or a communication medium, forexample, a storage medium such as a CD, an FD, or an MO, or acommunication medium such as a network. By providing such programs inthe computer readable format, processing corresponding to the programsis realized on the computer system.

Other objects, characteristics, and advantages of the invention will bemade apparent by more detailed explanations based on embodiments of theinvention described later and the attached drawings. A system in thisspecification means a logical set of plural apparatuses and is notlimited to a system in which the respective apparatuses are provided inan identical housing.

According to an embodiment of the invention, the imaging apparatus suchas a video camera having a GPS (Global Positioning System) deviceexecutes processing for setting positional information acquired in theGPS device as attribute information corresponding to image dataphotographed by the imaging unit and for storing the positionalinformation in the storing unit. Thus, in generating display informationindicating photographing position information of photographed imagedata, it is unnecessary to associate the display information with a GPSlog, it is possible to directly acquire the display information fromattribute information corresponding to the image data, and it ispossible to perform efficient display information generation processingwith light loads.

Moreover, according to another embodiment of the invention, thefrequency of photographing is monitored to calculate a frequency of useof the imaging apparatus per unit time and, when the frequency of use islower than a predetermined threshold, power is intermittently suppliedto the GPS device. Thus, wasteful power consumption in the GPS device isprevented and consumption of a battery is controlled. Intermittentdriving of the GPS device makes it possible to maintain a navigationmessage, which is data received from a GPS satellite, as a navigationmessage having an unexpired term of validity and to perform positioncalculation in a short time using the navigation message withoutperforming a new GPS satellite search.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram for schematically explaining processing executed byan imaging apparatus according to an embodiment of the invention;

FIG. 2 is a diagram for explaining an example of data processingexecuted in the imaging apparatus according to the embodiment;

FIG. 3 is a diagram for explaining an example of data processingexecuted in the imaging apparatus according to the embodiment;

FIG. 4 is a diagram for explaining an example of data processingexecuted in the imaging apparatus according to the embodiment;

FIG. 5 is a diagram for explaining a structure of the imaging apparatusaccording to the embodiment;

FIG. 6 is a diagram for explaining respective kinds of controlprocessing executed by the imaging apparatus according to theembodiment;

FIG. 7 is a flowchart for explaining a power supply control sequence ofa GPS module executed in the imaging apparatus according to theembodiment;

FIG. 8 is a diagram for explaining an amount of power consumption in aGPS device;

FIG. 9 is a diagram for explaining an amount of power consumption in theGPS device;

FIGS. 10A to 10C are diagrams for explaining data recording and displaydata generation processing executed by an imaging apparatus having ageneral GPS function;

FIGS. 11A and 11B are diagrams for explaining data recording and displaydata generation processing executed in the imaging apparatus accordingto the embodiment;

FIG. 12 is a flowchart for explaining a data recording processingsequence executed in the imaging apparatus according to the embodiment;

FIG. 13 is a flowchart for explaining a data display processing sequenceexecuted in the imaging apparatus according to the embodiment; and

FIG. 14 is a diagram for explaining an example of data displayprocessing executed in the imaging apparatus according to theembodiment.

DETAILED DESCRIPTION

Details of an imaging apparatus, a data recording method and a datadisplay control method, and a computer program according to embodimentsof the invention will be hereinafter explained with reference to theaccompanying drawings.

First, processing executed by an imaging apparatus according to anembodiment of the invention will be schematically explained withreference to FIG. 1. In FIG. 1, a video camera 110 that mainly performsmoving image photographing and a still camera 120 that performs stillimage photographing are shown as the imaging apparatus according to theembodiment. These imaging apparatuses include GPS modules 111 and 121.

Each of the GPS modules 111 and 121 is, for example, a packaged moduleincluding an antenna unit that receives a GPS radio wave, a signalconverting unit that converts the radio wave received, a calculatingunit that calculates positional information, a temporary storage unitthat stores a result of the calculation, and a communication unit thatexecutes communication with a main control unit (CPU) on an imagingapparatus body side.

The GPS modules 111 and 121 of the respective imaging apparatusesreceive radio waves from GPS satellites 130 a, 130 b, 130 c, and thelike, which are located in the outer space and transmit GPS positionalinformation, and acquire present latitude and longitude coordinates onthe Earth and reception time. A principle of this reception isequivalent to that of the general GPS reception system.

Each of the plural GPS satellites located in the outer space transmits anavigation message including positional information indicating aposition of the GPS satellite in the outer space and time information.The GPS modules 111 and 121 deduce the positional information from thisnavigation message. The navigation messages transmitted by the GPSsatellites in the outer space include ephemeris data (almanac andephemeris) serving as positional information of the satellites andsignal transmission time information.

The GPS modules 111 and 121 calculate a three-dimensional position (x,y, z) as positional information. In order to calculate a dimensionalposition, processing for capturing at least three GPS satellites isnecessary. In other words, it is necessary to receive navigationmessages from at least three GPS satellites, positions of which areconfirmed. Positions of the GPS modules 111 and 121 are determined usingreception information (the navigation messages) from these at leastthree GPS satellites by applying the triangulation method to theprocessing.

Steps for determining a present position of a GPS receiver using thetriangulation method are as follows.

[Step 1] GPS Satellite Capturing Processing

Data from at least three GPS satellites, from which navigation messagescan be received in the GPS modules 111 and 121, are received andpositions of the respective GPS satellites are checked.

[Step 2] GPS Module Position Determination Processing

Distances from the GPS modules 111 and 112 are calculated and positionsof the GPS modules with respect to the center of the Earth arecalculated on the basis of the triangulation method.

In the steps, the processing in step 2 can be executed according toarithmetic processing in the GPS modules. On the other hand, in theprocessing in step 1, that is, the processing for receiving data from atleast three GPS satellites, from which navigation messages can bereceived, and checking positions of the respective GPS satellites, it iseffective for reduction of processing time to acquire approximatepositional information of the GPS satellites in advance and apply thepositional information to the processing.

As described above, the navigation messages transmitted by the GPSsatellites include ephemeris data (almanac and ephemeris) serving aspositional information of the satellites. When the GPS modulescontinuously or intermittently perform data reception, it is possible toestimate present positions of the satellites by using data received inthe past. If it is possible to use the data received in the past, it ispossible to efficiently perform capturing of the GPS satellites in ashort time, that is, data reception from the GPS satellites. In otherwords, it is possible to quickly perform the GPS satellite capturingprocessing in step 1 above.

However, the navigation messages have a best-before-data set as a termof validity (three months for almanac data and two hours for ephemerisdata). When data within the term of validity is held, it is possible toestimate present positions of the satellites by using the data receivedin the past. Thus, it is possible to efficiently execute the processingin steps 1 and 2 above in a short time and quickly perform positioncalculation by the GPS modules 111 and 121. However, when data having anunexpired term of validity is not held, it is difficult to performefficient GPS position estimation to which acquired data applied. Thus,it is necessary to search for GPS satellite positions from thebeginning. If such position search is performed, it is difficult toreduce the processing time in step 1. As a result, it takes time toperform calculation of positions to which the GPS modules 111 and 121are applied.

If the GPS modules 111 and 121 are typically actuated to continuouslyreceive navigation messages, it is possible to typically hold navigationmessages having an unexpired term of validity and efficiently capturethe GPS satellites. However, for this purpose, power has to becontinuously supplied to the GPS modules to drive the GPS modules. Onthe other hand, operation power for the GPS modules 111 and 121 providedin the imaging apparatuses 110 and 120 is supplied from the batteries ofthe imaging apparatuses 110 and 120. Thus, there is a request forcontrolling consumption of the batteries as much as possible.

The imaging apparatuses 110 and 120 according to the embodiment meetsuch a request. Power supply to the GPS modules 111 and 121 iscontrolled according to a state of use of the imaging apparatuses 110and 120 by the user. This makes it possible to reduce power consumptionand increase, according to the state of use by the user, speed ofprocessing for acquiring positional information from the GPS modules.

An example of data processing executed in the imaging apparatusaccording to this embodiment will be explained with reference to FIGS. 2to 4. First, an example of processing at the time of image photographingwill be explained with reference to FIG. 2. As shown in the figure, animaging apparatus 200 has, as modes, a photographing mode for executingphotographing of a moving image or a still image and a reproduction modefor executing reproduction of photographed data.

In the photographing mode, as shown in FIG. 2, image data 201 isacquired by imaging processing in an imaging apparatus body. Moreover,positional information (latitude and longitude) 202 of a GPS module isacquired by the GPS module. The data-recording control unit 211 in theimaging apparatus stores these pieces of information in thephotographed-content storing unit 212 in association with each other. Inother words, the positional information (latitude and longitude) 202acquired by the GPS module is set as attribute data corresponding to therespective image data and stored in the photographed-content storingunit 212.

An example of processing in the reproduction mode for executingreproduction of photographed data will be explained with reference toFIG. 3. In FIG. 3, four examples of display data (a) to (d) displayed ona monitor of the imaging apparatus in the reproduction mode are shown.These display data (a) to (d) are generated according to the control bya data-display control unit 221 in the imaging apparatus. Thedata-display control unit 221 acquires positional information recordedas data in the photographed-content storing unit 212, that is, imagedata and as attribute data of the image data, information in a mapinformation database 222 including data such as maps, addresses, andphotographing spot information serving as data associated with latitudeand longitude information, and positional information inputted from aGPS module 223 and generates display data.

For example, the display data (a) is an example of display in which mapinformation is displayed on the monitor to present the presentpositional information to the user. In this display, the presentpositional information is inputted from the GPS module 223 andinformation clearly indicating a present position is displayed on a mapin accordance with the positional information inputted. This isequivalent to an example of display of general navigation information.

The display data (b) is an example of display in which the photographedimage data stored in the photographed-content storing unit 212 isdisplayed and a photographing place is displayed in characters on thebasis of map data, which is acquired from the map information database222 on the basis of the positional information recorded as the attributedata in association with the image data, and spot information.

The display data (c) is an example of display in which the photographedimage data stored in the photographed-content storing unit 212 arearranged in an order of a photographing sequence and display forindicating transition of a photographing position on a map is performed.Photographed data are displayed on the map as thumbnail images.

The display data (d) is an example of display in which photographed dataand map data are displayed in combination. On the basis of positionalinformation recorded as attribute data of the photographed data, a mapof an area corresponding to the positional information is displayed in apart of the monitor.

Moreover, in the photographing mode, as shown in FIG. 4, it is possibleto perform processing for collectively storing photographed contents infolders corresponding to photographing places on the basis of positionalinformation serving as attribute data corresponding to photographeddata. For example, it is possible to collectively store photographeddata corresponding to a specific area in one file according toprocessing in which the data-recording control unit 211 stores data in acertain latitude and longitude range in one folder, for example, afolder with a title [France, 2006 Summer] on the basis of latitude andlongitude information acquired as attribute information corresponding toa photographed image. Since photographing date and time data is alsogiven to the photographed data as attribute information, it is alsopossible to classify photographed data on the basis of time informationof the photographing date and time data.

The examples of data processing executable in the imaging apparatus havebeen explained. Various other kinds of processing are possible. Forexample, it is possible to support photographing by the user on thebasis of positional information from the GPS module even at the time ofthe photographing mode. For example, it is possible to performprocessing for indicating on the monitor whether it is possible toreceive a GPS radio wave in a place where photographing is presentlyperformed, processing for illustrating a present position on a screenmap as in the car navigation, or processing for displaying place nameinformation of a present position in a photographing screen. It ispossible to realize these kinds of processing by causing the imagingapparatus to execute the processing by the data-display control unit 221explained with reference to FIG. 3 at the time of photographing.

A structure of the imaging apparatus according to this embodiment willbe explained with reference to FIG. 5. In FIG. 5, components of theimaging apparatus having the GPS module are divided into a photographingapparatus body 310, a power-supply control unit 320, a GPS module 330,and a power supply (battery) 350.

The imaging apparatus body 310 has a function of a video camera or astill camera. The imaging apparatus body 310 has display data generationprocessing functions such as imaging processing, reproduction ofphotographed data, and generation and output of various kinds of displayinformation based on the photographed data. The imaging apparatus body310 includes a main control unit (a host CPU) 311, a data storing unit(a flash memory) 312 that records photographed data and the like, amemory (an SDRAM) 314 that performs primary data storage, and a displayunit (a monitor) 313.

The power-supply control unit 320 is constituted by, for example, afront panel system. The power-supply control unit 320 includes afront-panel control unit 321, an input unit 322 including variousswitches such as a power supply switch, and an output unit 322 thatperforms display of photographing information. The GPS module 330includes a GPS device 340 and a power-supply-voltage converter 331. TheGPS device 340 is inputted with electric power converted into apredetermined voltage via the power-supply-voltage converter 331 anddriven. The GPS device 340 executes satellite capturing and navigationmessage acquisition processing. The GPS device 340 includes a dataprocessing unit 341 that executes navigation data recording, positioncalculation processing, and the like and a memory (an SRAM) 342 thatstores navigation data acquired and positional data calculated.

The power supply (the battery) 350 supplies electric power to theimaging apparatus body 310, the power-supply control unit 320, and theGPS module 330. However, as described later, power supply to the GPSmodule 330 is controlled according to a state of execution of imagingprocessing by the user. Electric power for self-refresh processing issupplied to the memory (the SDRAM) 314 of the imaging apparatus body 310and the memory (the SRAM) 342 of the GPS device 340.

Control for supply of electric power for driving the GPS device 340 willbe explained. Electric power for driving the GPS device 340 is inputtedto the GPS device 340 via the power-supply-voltage converter 331. Theelectric power for driving the GPS device 340 is controlled on the basisof a state of execution of photographing by the user measured in themain control unit (the host CPU) 311 of the imaging apparatus body 310.

The main control unit (the host CPU) 311 of the imaging apparatus body310 measures frequency of photographing by the user and judges whetherphotographing is executed at frequency higher than a predeterminedthreshold. When it is judged that the photographing is executed at highfrequency higher than the predetermined threshold, the main control unit(the host CPU) 311 issues a control command to the front-panel controlunit 321 to execute continuous power supply to the GPS device 340. Thefront-panel control unit 321 controls the power-supply-voltage converter331 of the GPS module 330 to execute continuous power supply to the GPSdevice 340. In a period of the continuous power supply, continuousreception of navigation messages and position calculation processing areexecuted in the GPS device 340.

On the other hand, when it is judged in the main control unit (the hostCPU) 311 of the imaging apparatus body 310 that the photographing by theuser is executed at low frequency lower than the predeterminedthreshold, the main control unit (the host CPU) 311 stops the continuouspower supply to the GPS device 340 and outputs a control command to thefront-panel control unit 321 to execute intermittent power supply. Thefront-panel control unit 321 controls the power-supply-voltage converter331 of the GPS module 330 to execute intermittent power supply to theGPS device 340. In a period of the intermittent power supply,intermittent reception of navigation messages and position calculationprocessing are executed in the GPS device 340.

In other words, the GPS device 340 performs an intermittent positioningoperation independently regardless of whether a power supply for theimaging apparatus body is on or off. When the power-supply control unit(the front panel system) 320 instructs to turn on a power supply for theGPS device 340, the power-supply-voltage converter 331 supplies electricpower to the GPS device 340. The GPS device 340 starts a positioningoperation.

A flow of basic processing will be explained with reference to a diagramshown in FIG. 5. First, when the imaging apparatus body 310 is turned onaccording to user operation of the input unit 322 of the power-supplycontrol unit (the front panel system) 320, the GPS device 340 in the GPSmodule 330 is also turned on according to a command from thepower-supply control unit (the front panel system) 320, that is,electric power is supplied.

When the power supply is started, first, the GPS device 340 loads backupdata of navigation data necessary for capturing GPS satellites from thedata storing unit 312 of the imaging apparatus body 310 and uses thebackup data for capturing of GPS satellites. In other words, navigationdata, that is, almanac and ephemeris data acquired by the GPS device 340in the past are stored in the data storing unit 312 serving as anonvolatile memory of the imaging apparatus body 310. The GPS device 340acquires these data and captures GPS satellites.

However, as described above, terms of validity are set for therespective navigation data. When the terms of validity have expired,since it may be impossible to apply navigation messages of thenavigation data acquired, the GPS device 340 needs to capture GPSsatellites at random.

When the GPS device 340 succeeds in capturing of GPS satellitesnecessary for calculating positional information, latest navigation dataacquired by the GPS device 340 and positional information calculated bythe GPS device 340 are inputted to the imaging apparatus body 310. Thecontrol unit (the host CPU) 311 of the imaging apparatus body 310outputs a command to the power-supply control unit (the front panelsystem) 320 to cause the GPS module 331 to shift to an intermittentdriving state. Then, the GPS module 331 shifts to the intermittentdriving state according to an instruction from the power-supply controlunit (the front panel system) 320. Thereafter, GPS device 340 continuesan intermittent measurement operation independently from transition ofstates of on and off of power supply to the imaging apparatus body 310.

In this case, latest positional information serving as positioninginformation based on a navigation message acquired anew in the dataprocessing unit 341 of the GPS device 340 is stored in the memory (theSRAM) 342 in the GPS device 340. When the imaging apparatus body 310 isturned on next time, the positional information stored in the memory(the SRAM) 342 in the GPS device 340 is read out by a GPS controlapplication running on the imaging apparatus body 310.

In this data readout time, the control unit (the host CPU) 311 judgeswhether the positional information and the navigation message acquiredare newer than the data stored in the data storing unit 312 serving as anonvolatile memory of the imaging apparatus body 310. When thepositional information and the navigation message are newer, the controlunit (the host CPU) 311 stores the new acquired data in the data storingunit 312 and executes data update.

A constitution for control of various kinds of data processing executedin the imaging apparatus according to this embodiment will be explainedwith reference to FIG. 6. Control modules that execute main dataprocessing control in the imaging apparatus according to the embodimentof the invention are shown in FIG. 6. As the control modules, aphotographing-processing control unit 401, a GPS-control processing unit402, a data-recording control unit 403, and a data-display control unit404 are shown in FIG. 6. Control by these units is basically controlexecuted by the main control unit (the host CPU) 311 of the imagingapparatus body shown in FIG. 5. However, for convenience of explanation,the respective kinds of control are shown by category. When programs forexecuting the respective kinds of controls are read out and executed bythe main control unit (the host CPU) 311, control for various kinds ofhardware is performed and respective kinds of processing are executed.

The photographing-processing control unit 401 executes photographingprocessing similar to that of a general camera. Photographing processingimage data is recorded in the photographed-content storing unit 212 viathe data-recording control unit 403. The data-recording control unit 403further inputs positional information and time information (a timestamp) acquired by a GPS module 412 under the control in the GPS-controlprocessing unit 402. The data-recording control unit 403 sets thesekinds of information acquired by the GPS module as attribute informationcorresponding to photographed image data and records the informationacquired by the GPS module in the photographed-content storing unit 212.

The GPS-control processing unit 402 executes power supply control forthe GPS module 412 via a power-supply control unit 411 and provides thedata-recording control unit 403 with the positional information acquiredin the GPS module 412.

The data-display control unit 404 acquires the photographed image datarecorded in the photographed-content storing unit 212 and the attributeinformation corresponding to the image data. The data-display controlunit 404 further acquires information from the map information database222 including data such as maps, addresses, and photographing spotinformation serving as data associated with latitude and longitudeinformation. The data-display control unit 404 generates displayinformation that is presented on a display 423. For example, thedata-display control unit 404 performs processing for, for example,superimposing thumbnails of plural images photographed in a travel ofthe user on locus information shown on a map and presenting thethumbnails.

For example, the data-display control unit 404 executes processing forinvoking photographed contents recorded in the photographed-contentstoring unit 212 in response to a user request and combining thephotographed contents with map information and place name informationheld in the map information database 222 to display the photographedcontents and processing for automatically classifying the photographedcontents recorded in the photographed-content storing unit 212 withpositional information as a key and displaying a result of theclassification on the display 423.

Details of control of the GPS module, in particular, power supplycontrol processing executed in the GPS-control processing unit 402, inparticular, data recording processing in the data-recording control unit403, and data display processing in the data-display control unit 404will be explained.

[(1) GPS Module Control Processing]

First, a power supply control sequence for the GPS module executed inthe GPS-control processing unit 402 will be explained with reference toa flowchart shown in FIG. 7. Processing control according to this flowis processing executed by the control by the main control unit (the hostCPU) 311 of the imaging apparatus body 310. First, when the imagingapparatus is turned on by the user, in step S101, the main control unit(the host CPU) 311 initializes setting necessary for operation in theGPS module.

When the initialization of the GPS module is completed, in step S102,according to the control by the main control unit (the host CPU) 311 ofthe imaging apparatus body, an application on the imaging apparatus sideinquires of the GPS module about a term of validity of a latestnavigation message held by the GPS module in the memory. The applicationjudges whether the acquired navigation message is data having anunexpired term of validity or data having an expired term of validity.

When the term of the navigation message has already expired, the maincontrol unit (the host CPU) 311 proceeds to step S121, drives the GPSdevice regardless of timing of a photographing action, and causes theGPS device to update the navigation message. After the update of thenavigation message, the application on the imaging apparatus sidemonitors frequency of photographing by the user. An application executedin the imaging apparatus body holds a predetermined photographingfrequency threshold and compares a state of photographing processingactually performed by the user with this threshold. For example, theapplication monitors a photographing state of the user for nimages/minute in still image photographing processing and for nframes/minute in moving image photographing processing, acquiresphotographing frequency data, and compares the photographing frequencydata acquired with the threshold held in advance.

When it is judged in the comparison with the threshold that thefrequency of photographing by the user is low (step S103: Yes), the maincontrol unit (the host CPU) 311 proceeds to step S122 and executescontrol to intermittently drive the GPS device in order to control powerconsumption. In other words, the main control unit (the host CPU) 311executes intermittent power supply to the GPS device and causes the GPSdevice to intermittently execute reception of navigation messages andcalculation of positions.

Specifically, as explained with reference to FIG. 5 above, when it isjudged in the main control unit (the host CPU) 311 of the imagingapparatus body 310 that photographing at low frequency of photographingby the user lower than the predetermined threshold is executed, the maincontrol unit (the host CPU) 311 outputs a control command to thefront-panel control unit 321 to stop continuous power supply to the GPSdevice 340 and execute intermittent power supply. The front-panelcontrol unit 321 controls the power-supply-voltage converter 331 of theGPS module 330 to execute intermittent power supply to the GPS device340. In a period of the intermittent power supply, intermittentreception of navigation messages and position calculation processing areexecuted in the GPS device 340.

On the other hand, when it is judged in the comparison with thethreshold that the frequency of photographing by the user is not low(step S103: No), the main control unit (the host CPU) 311 proceeds tostep S104 and controls the GPS module to typically perform satellitecapturing in order to acquire highly accurate positional informationthat follows photographing timing as much as possible.

In other words, the main control unit (the host CPU) 311 of the imagingapparatus body 310 outputs a control command to the front-panel controlunit 321 to execute continuous power supply to the GPS device 340. Thefront-panel control unit 321 controls the power-supply-voltage converter331 of the GPS module 330 to execute continuous power supply to the GPSdevice 340. In a period of the continuous power supply, continuousreception of navigation messages and position calculation processing areexecuted in the GPS device 340.

Thereafter, in step S105, the main control unit (the host CPU) 311judges whether the photographing action by the user is continued(including a state in which the power supply is temporarily turned off).When the photographing action is continuously executed, the main controlunit (the host CPU) 311 repeatedly executes the processing in step S102and the subsequent steps, that is, the processing from the check of aterm of validity of a navigation message. In a period when thephotographing processing is executed, in step S102, the main controlunit (the host CPU) 311 of the imaging apparatus body 310 periodicallyperforms verification of a term of validity of an acquired navigationmessage in the GPS device. When the term of validity of the acquirednavigation message has been expired, the main control unit (the hostCPU) 311 proceeds to step S121 and causes the GPS device to executeprocessing for updating navigation data.

When it is judged in step S105 that the photographing action by the useris not continued, for example, when the power supply of the imagingapparatus is turned off and is not turned off again for a certain lengthof time, the main control unit (the host CPU) 311 stops the power supplyto the imaging apparatus body 310 and the GPS module and completes theprocessing.

An amount of power consumption in the GPS device will be explained withreference to FIGS. 8 and 9. FIG. 8 is a graph of a change of an amountof power consumption in the GPS device at the time when the power supplyto the GPS device is turned on, capturing of GPS satellites is executed,and navigation messages are continuously acquired. The abscissaindicates time t (sec) and the ordinate indicates an electric current(mA) corresponding to the amount of power consumption of the GPS device.

Power supply to the GPS device is started at time (t0). At time (t0), itis assumed that a term of validity of an acquired navigation message hasbeen expired and it may be impossible to use the navigation message. Inthis case, the GPS device executes processing for capturing plural GPSdevices necessary for position measurement. In other words, the GPSdevice searches for plural GPS device and needs to receive navigationmessages from a GPS satellite found as a result of the search. Anelectric current of about 70 mA is consumed for this processing.

When the GPS device succeeds in capturing of a GPS satellite and anavigation message having an unexpired term of validity is recorded inthe memory at time (t1), thereafter, it is unnecessary to search for anew GPS satellite. It is possible to shift to a tracking mode fortracking the captured GPS satellite. In this tracking mode, it ispossible to perform tracking to which a navigation message having anunexpired term of validity is applied. The electric current consumptionis reduced to about 30 mA. When the GPS device continuously receivesnavigation messages, it is necessary to continuously supply an electriccurrent of 30 mA to the GPS device.

In an example shown in FIG. 9, power supply to the GPS device isexecuted in an intermittent mode. (1) in FIG. 9 indicates timing whenthe application on the imaging apparatus body side acquires positionalinformation from the GPS module. When the power supply is on, theapplication acquires positional information from the GPS module. (2) inFIG. 9 indicates a transition in states of on and off of the powersupply of the GPS device. In this example, since the power supply isexecuted in the intermittent mode, on and off of the power supply isswitched in accordance with predetermined control timing for theintermittent mode. (3) in FIG. 9 indicates a change in an amount ofpower consumption in the GPS module.

Power supply to the GPS device is started at time (ta). At time (ta), asat time (t0) in FIG. 8, it is assumed that a term of validity of anacquired navigation message has been expired and it may be impossible touse the navigation message. In this case, the CPS device executesprocessing for capturing plural GPS devices necessary for positionmeasurement. In other words, the GPS device searches for plural GPSdevices and needs to receive a navigation message from a GPS satellitefound as a result of the search. An electric current of about 70 mA isconsumed for this processing.

When the GPS device succeeds in capturing a GPS satellite and anavigation message having an unexpired term of validity is recorded inthe memory at time (tb), thereafter, it is unnecessary to search for anew GPS satellite. It is possible to shift to a tracking mode fortracking the captured GPS satellite. In this tracking mode, it ispossible to perform tracking to which a navigation message having anunexpired term of validity is applied. The electric current consumptionis reduced to about 30 mA.

At time (tc), when it is judged in the monitoring processing of theapplication on the imaging apparatus side that frequency ofphotographing by the user is lower than the threshold set in advance,power supply to the GPS device is set in the intermittent mode and thepower supply to the GPS device is temporarily stopped. Thereafter, attime (td), at timing when the application executes a request foracquisition of positional information to the GPS device, power supply tothe GPS device is resumed. At this point, power consumption of the GPSdevice occurs.

However, when a period in which power supply to the GPS device isstopped is not long, the acquired navigation message is maintainedwithin the term of validity. It is possible to perform GPS satellitetracking, to which a navigation message having an unexpired term ofvalidity is applied, without executing search for a new GPS satellite.In other words, it is possible to receive a navigation message in thetracking mode and perform processing at low power consumption. In aperiod of time (td) to (te), when the GPS device succeeds in acquisitionof a new navigation message, stores the navigation message in thememory, and provides the application with positional informationcalculated, power supply to the GPS device is stopped and powerconsumption is reduced to 0. Power consumption is reduced by executingprocessing in such an intermittent mode. When a period in which powersupply to the GPS device is stopped is not long, the acquired navigationmessage is maintained within the term of validity. This makes itpossible to execute acquisition of a new navigation message from the GPSsatellite, to which a navigation message having an unexpired term ofvalidity is applied, in a short time.

Timing for resuming power supply to the GPS device (e.g., time (td) inFIG. 9) is timing controlled by the control unit of the imagingapparatus body. In the example shown in FIG. 9, timing for resumingpower supply to the GPS device is set to coincide with timing when theimaging apparatus body inputs positional information from the GPSdevice. Various settings are possible for a setting for an interval ofon and off of the power supply to the GPS device in this intermittentcontrol. For example, on and off of the power supply may be repeated ata predetermined fixed time interval. Time shorter than the term ofvalidity of the navigation message may be set as longest time in whichthe power supply is off. Such a setting makes it possible to typicallymaintain a state in which a navigation message having an unexpired termof validity can be used.

In the example explained in the embodiment described above, the GPSmodule is built in the imaging apparatus. However, it is also possibleto apply a GPS system externally attached to the imaging apparatus byUSB connection or the like when the power supply is shared by theimaging apparatus body and the GPS module. An effect of power reductionand an increase in speed of the processing for acquiring positionalinformation are realized.

Moreover, in the example explained the embodiment, the power supply isshared by the GPS module and the imaging apparatus body. However, it isalso possible to realize the effect of controlling power consumption ofthe GPS module even when power supplies are separately set for the GPSmodule and the imaging apparatus body. Speed of restart is improved andan increase in speed of the processing for acquiring positionalinformation is realized.

[(2) Data Recording and Display Control Processing]

Details of the data recording processing in the data-recording controlunit 403 and the data display processing in the data-display controlunit 404 in FIG. 6 will be explained.

As explained above with reference to FIG. 6, image data photographed inthe photographing-processing control unit 401 is recorded in thephotographed-content storing unit 212 via the data-recording controlunit 403. Moreover, the data-recording control unit 403 inputspositional information and time information (a time stamp) acquired bythe GPS module 412 under the control in the GPS-control processing unit402, sets these kinds of information acquired by the GPS module asattribute information corresponding to photographed image data, andrecords the information acquired by the GPS module in thephotographed-content storing unit 212.

The data-display control unit 404 acquires the photographed image dataand the attribute information corresponding to the image data recordedin the photographed-content storing unit 212. The data-display controlunit 404 further acquires information from the map information database222 including data such as maps, addresses, and photographing spotinformation serving as data associated with latitude and longitudeinformation. The data-display control unit 404 generates displayinformation that is presented on the display 423. For example, thedata-display control unit 404 performs processing for, for example,superimposing thumbnails of plural images photographed in a travel ofthe user on locus information shown on a map and presenting thethumbnails.

In recording the photographed image data in the photographed-contentstoring unit 212, the data-recording control unit 403 in the imagingapparatus according to this embodiment inputs the positional informationand the time information (the time stamp) acquired by the GPS module412. The data-recording control unit 403 sets and records these kinds ofinformation acquired by the GPS module as attribute informationcorresponding to the photographed image data.

As explained in the section of the background art above, the camera inthe past having a general GPS function typically positions a presentposition with the GPS device and records GPS log data including acquiredpositional information in the memory. Processing for recording thepositional information acquired by the GPS module as attributeinformation of the photographed image data is not performed. Therefore,it is necessary to execute processing for associating the positionalinformation with the photographed image data when processing fordisplaying the data is performed. This causes an increase in loads ofthe data display processing.

A method in the past and a method according to this embodiment will beexplained. The method in the past is a method of separately recordingGPS log data and attribute data, which is recorded in association withphotographed data, in the storing unit. The method according to thisembodiment is a method of setting positional information, timeinformation, and the like acquired from GPS log data as attribute data,which is recorded in association with photographed data, and recordingthe positional information, the time information, and the like in thestoring unit.

First, the method in the past will be explained with reference to FIGS.10A to 10C. Data structures of the GPS log data separately recorded inthe storing unit of the imaging apparatus and the attribute datarecorded in association with the photographed data in the past will beexplained. Further, processing for associating data necessary inexecuting display processing using these recorded data, for example,processing for analyzing a photographing position for the photographeddata and identifiably displaying the photographing position on a mapwill be explained.

GPS log data including positional information and time informationacquired from navigation data continuously received by a GPS is shown inFIG. 10A. Attribute information of photographed data recorded inassociation with an image photographed in photographing processing bythe user is shown in FIG. 10B. Photographing time information isrecorded in the attribute information. As information recorded in a GPSlog, latitude, longitude, and time are recorded in association withnames of points (A, B, C, etc.) serving as identification informationset as index data. The GPS module continuously positions points in orderfrom the point A and repeats acquisition of information.

On the other hand, in the photographing apparatus body, photographedcontents (a still image or a moving image) are saved as a file in thestoring unit according to a photographing action of the user. In thissaving processing, a time stamp serving as photographing timeinformation is recorded in the photographed contents. In an exampleshown in FIG. 10B, photographing date and time information is recordedin association with names of points (1, 2, etc.) serving asidentification information of an image photographed by the user.

The GPS log (a) and the photographed data attribute information (b) areheld in the storing unit as separate independent data files. Forexample, in performing processing for displaying photographed data(thumbnails) on a map in association with photographing positions andpresenting locus information to the user, the user transfers the GPS log(a), the photographed data attribute information (b), and thephotographed image data to a PC and executes data processing based onthese data transferred to generate display information using dedicatedPC application software.

First, the PC application performs processing for calculatingphotographing positions of respective photographed images included inthe photographed data attribute information (b). This processing isperformed by associating the photographed time information in thephotographed data attribute information (b) with the time informationincluded in the GPS log (a). For example, data [No. 1, point 1] includedin the photographed data attribute information (b) is data photographedat time [T1]. It is assumed that T1 is within time Ta to Tb in log dataincluded in the GPS log (a).

In this case, the photographing point 1 at time T1 is calculated from aposition (a point “a”) at time Ta and a position (a point “b”) at timeTb in the log data included in the GPS log. According to so-calledlinear interpolation processing, the photographing point 1 at time T1 iscalculated from two GPS logs, that is, positional information (Xa, Ya)of the point A and positional information (Xb, Yb) of the point B.Latitude and longitude (X1, Y1) of the photographing point 1 ofphotographing performed at time T1 are calculated from the followingequation.α=(T1−Ta)/(Tb−Ta)X1=(Xb−Xa)/α+XaY1=(Yb−Ya)/α+Ya

The equation is an equation for calculating a position at time T1 intime Ta to Tb (latitude and longitude (X1, Y1) at the point 1) accordingto linear interpolation by applying a position at time Ta (the point A)and a position at time Tb (the point B) included in the GPS log, whichare accurately identified, to the processing.

Similarly, a photographing point 2 at time T2 included in thephotographed data attribute information is calculated from two GPS logs,that is, positional information (Xd, Yd) of the point D and positionalinformation (Xe, Ye) of the point E. Latitude and longitude (X2, Y2) ofthe photographing point 2 of photographing performed at time T2 arecalculated from the following equation.β=(T2−Td)/(Te−Td)X2=(Xe−Xd)/β+XdY2=(Ye−Yd)/β+Yd

The equation is an equation for calculating a position at time T2 intime Td to Te (latitude and longitude (X2, Y2) at the point 2) accordingto linear interpolation by applying a potion at time Td (the point D)and a position at time Te (the point E) included in the GPS log, whichare accurately identified, to the processing.

Display information shown in FIG. 10C is generated and displayed on adisplay on the basis of photographing position information of respectiveimages calculated in this way. The display information shown in FIGS.10A to 10C is data indicating a moving locus of the user. This is anexample in which positional information of points positioned by the GPSmodule and photographing points is presented on a map and a course iscalculated on the basis of time information and indicated by arrows.

In this display processing, first, map information corresponding tophotographing positions of image data calculated by the processingdescribed above is acquired from the map information database. Icons(black circles) indicating the positions of the points A, B, C, and thelike included in the GPS log are indicated on a map. Icons (blacksquares) indicating a position (latitude and longitude (X1, Y1) of thepoint 1) and a position (latitude and longitude (X2, Y2) of the point 2)calculated by the processing are displayed on the map. Arrows connectingthe respective icons displayed are displayed. In this way, the course ispresented to the user.

As described above, when the GPS log data and the attribute informationcorresponding to the photographed image data are managed as separaterecording data, in displaying moving locus information, it is necessaryto perform processing for associating the GPS log data and the attributeinformation corresponding to the photographed image data, resulting ininefficient and heavy-load processing.

The data recording and display control processing in the imagingapparatus according to this embodiment will be explained with referenceto FIGS. 11A and 11B. Details of the data recording processing in thedata-recording control unit 403 and the data display processing in thedata-display control unit 404 in FIG. 6 will be explained.

Image data photographed in the photographing-processing control unit 401shown in FIG. 6 is recorded in the photographed-content storing unit 212via the data-recording control unit 403. The data-recording control unit403 inputs positional information and time information acquired by theGPS module 412 in this recording processing, sets these kinds ofinformation acquired by the GPS module as attribute informationcorresponding to the photographed image data, and records theinformation acquired by the GPS module in the photographed-contentstoring unit 212.

In FIG. 11A, a data structure of photographed data attribute informationgenerated by the data-recording control unit 403 shown in FIG. 6 andrecorded in the photographed-content storing unit 212 is shown. In thephotographing apparatus body, photographed contents (a still image or amoving image) are saved as a file in the storing unit according to aphotographing action of the user. In this saving processing, a timestamp serving as photographing time information is recorded in thephotographed contents. Moreover, the data-recording control unit 403inputs the positional information and the time information acquired bythe GPS module 412 and records the positional information and the timeinformation as attribute information corresponding to the photographedcontents (the still image or the moving image). As the time information,a time stamp set in the imaging apparatus body or time informationacquired by a GPS is selected and recorded.

The data-display control unit 404 shown in FIG. 6 can apply theinformation recorded in the photographed-content storing unit 212, thatis, the photographed data attribute information shown in FIG. 11A to theprocessing, generate, for example, display information shown in FIG.11B, and present the display information on the display. In generatingthe display information, it is unnecessary to perform, for example, theprocessing for associating the display information with the GPS log dataexplained with reference to FIGS. 10A to 10C above. It is possible togenerate display data according to simple processing.

The photographed-data attribute information shown in FIG. 11A isacquired. Data such as map information serving as data associated withlatitude and longitude information included in the photographed-dataattribute information is acquired from the map information database 222and presented on the display. Photographing points of the photographeddata attribute information shown in FIG. 11A are displayed as icons(black squares). Moreover, arrows are displayed in accordance with thetime information included in the photographed data attribute informationshown in FIG. 11A.

As described above, the processing executed in the data-display controlunit 404 is processing to which only the information included in thephotographed data attribute information shown in FIG. 11A is applied.This is remarkably light processing compared with the processingexplained with reference to FIGS. 10A to 10C above. Therefore, it ispossible to perform processing in the control unit (the main CPU) on theimaging apparatus side surely and in a short time without performingprocessing for, for example, outputting data to the PC or the like andgenerating display data in an application on the PC side.

Processing sequences of the data recording processing and the datadisplay processing executed in the imaging apparatus according to thisembodiment will be explained with reference to FIGS. 12 and 13. First,the processing sequence of the data recording processing executed in theimaging apparatus according to this embodiment will be explained withreference to a flowchart shown in FIG. 12.

In step S201, photographing processing is executed by the user.Photographing processing control is executed according to the control bythe photographing-processing control unit 401 shown in FIG. 6. In stepS202, processing for acquiring positional information in the GPS moduleis executed. The processing for acquiring positional information in theGPS module is executed under the processing control by the GPS-controlprocessing unit 402 shown in FIG. 6. As explained above, power supply tothe GPS device is controlled according to frequency of photographing bythe user. The processing for acquiring positional information isperformed as processing with electric power saved.

In step S203, the data-recording control unit 403 shown in FIG. 6executes input of photographed image data and input of information fromthe GPS module and executes processing for setting positionalinformation and time information inputted from the GPS module asattribute information corresponding to the photographed image data andrecording the positional information and the time information in therecording unit as attribute information corresponding to thephotographed image data. In other words, the data-recording control unit403 generates the attribute information shown in FIG. 11A and recordsthe attribute information in the storing unit.

The processing sequence of the data display processing executed in theimaging apparatus according to this embodiment will be explained withreference to FIG. 13. This processing is processing executed in thedata-display control unit 404 shown in FIG. 6. First, in step S301, thedata-display control unit 404 acquires the attribute information of thephotographed image data recorded in the photographed-content storingunit 212 shown in FIG. 6. This data is the data shown in FIG. 11A. Theattribute information includes positional information and timeinformation associated with respective photographed images.

In step S302, the data-display control unit 404 acquires, on the basisof the positional information included in the attribute information ofthe photographed image data, a map of positions corresponding to thepositional information from the map database and displays the map on thedisplay. Moreover, in step S303, the data-display control unit 404generates display information (locus information, etc.) on the basis ofthe positional information and the time information included in theattribute information of the photographed image data and outputs thedisplay information. For example, the data-display control unit 404outputs the display information shown in FIG. 11B.

It is possible to execute the data recording processing explained withreference to the flow shown in FIG. 12 and the data display processingexplained with reference to the flow in FIG. 13 sequentially or inparallel. In other words, it is possible to execute processing foracquiring photographing operation and positioning information andrecording these pieces of information and processing for generatingdisplay information, to which recorded data is applied, sequentially oras parallel processing.

In the imaging apparatus according to this embodiment, it is possible toefficiently execute generation of complicated display data by applyingthe photographed data attribute information shown in FIG. 11A to theprocessing. An example of generation of display data will be explainedwith reference to FIG. 14.

An example shown in FIG. 14 is an example of display processing inwhich, when there are plural different photographed content files, forexample, photographed content files different temporally from oneanother, these files are merged, sort processing is executed whennecessary, and, for example, thumbnails and locus information arecollectively presented on the basis of plural photographed contents.

In (1) in FIG. 14, data obtained by plotting thumbnails photographed byMr. A when he traveled France in July 2004 on a map is shown. In (2) inFIG. 14, a result obtained by plotting contents photographed when Mr. Atraveled France on a slightly different route eight months later (March2005) is shown. It is possible to generate these display data byapplying the photographed data attribute information shown in FIG. 11Ato the processing. In other words, it is possible to realize the displaydata by displaying thumbnails of photographed data instead of the iconsindicating the photographing points of the locus information shown inFIG. 11B.

Moreover, it is possible to generate display data in (3) in FIG. 14 byapplying attribute information included in a photographed image datafile corresponding to the display data in (1) in FIG. 14 and a differentphotographed image data file corresponding to the display data in (2) inFIG. 14 to the processing. For example, in the photographed image datafile corresponding to the display data in (1) in FIG. 14, attributeinformation corresponding to images of the photographed image data file,that is, the photographed data attribute information including latitude,longitude, and time information shown in FIG. 11A is included. In thephotographed image data file corresponding to the display data in (2) inFIG. 14, photographed data attribute information including latitude,longitude, and time information corresponding to images of thephotographed image data file is included.

The data-display control unit 404 shown in FIG. 6 is capable ofgenerating, for example, time-series attribute data, in which pieces ofattribute information corresponding to plural image files are combined,by merging these two kinds of photographed data attribute informationand executing sort processing when necessary. It is possible to generatethe display data shown in (3) in FIG. 14, that is, one display data, towhich plural different content data files are applied, by executing thedisplay information generation processing explained with reference toFIGS. 11A and 11B or FIG. 13 on the basis of such attribute data merged.

The display data shown in (3) in FIG. 14 is imaginarily created on thebasis of the two data in (1) and (2) in FIG. 14. The display data in (3)in FIG. 14 is a summary of all Mr. A's travels to France. In this way,the imaging apparatus according to this embodiment directly recordspositional information acquired by the GPS as the attribute informationcorresponding to the photographed data. Thus, it is possible toefficiently calculate photographing positions corresponding torespective images simply by acquiring the attribute information. It isalso possible to easily and efficiently generate various display dataand present the display data.

The generation of such display data is easily realized in the imagingapparatus. Thus, for example, it is also possible to load photographedcontent information of the same format held in PCs or otherphotographing apparatuses to the imaging apparatus owned by the userhimself, generate display data on the basis of the data loaded, andoutput the display data.

The invention has been explained in detail with reference to thespecific embodiment of the invention. However, it is obvious that thoseskilled in the art can perform modifications and substitutions of theembodiment without departing from the spirit of the invention. Theinvention has been disclosed in a form of illustration and should not beinterpreted limitedly. To judge the spirit of the invention, theappended claims should be taken into consideration.

It is possible to execute the series of processing explained in thespecification using hardware or software or a composite constitution ofthe hardware and the software. In executing the processing by software,it is possible to install a computer program having a processingsequence recorded therein in a memory in a computer built in dedicatedhardware and cause the computer to execute the computer program orinstall the computer program in a general-purpose computer capable ofexecuting various kinds of processing and cause the computer to executethe computer program.

For example, it is possible to record the computer program in a harddisk or a ROM (Read Only Memory) serving as a recording medium inadvance. Alternatively, it is possible to temporarily or permanentlystore (record) the computer program in a removable recording medium suchas a flexible disk, a CD-ROM (Compact Disc Read Only Memory), an MO(Magneto optical) disk, a DVD (Digital Versatile Disc), a magnetic disk,or a semiconductor memory. It is possible to provide such a removablerecording medium as so-called package software.

In addition to installing the computer program in the computer from theremovable recording medium, it is also possible to transfer the computerprogram from a download site to the computer by radio or transfer thecomputer program from the download site to the computer by wire via anetwork such as the Internet. The computer can receive the computerprogram transferred in that way and install the computer program in arecording medium such as a hard disk built in the computer.

The various kinds of processing described in this specification may beexecuted not only in time series according to the above description butalso in parallel or individually according to processing capability ofan apparatus that executes the processing or when necessary. The systemin this specification is a logical set of plural apparatuses and is notlimited to a system in which the respective apparatuses are provided inan identical housing.

As explained above, according to an embodiment of the invention, theimaging apparatus such as a video camera having a GPS (GlobalPositioning System) device executes processing for setting positionalinformation acquired in the GPS device as attribute informationcorresponding to image data photographing in the imaging unit andstoring the positional information in the storing unit. Thus, ingenerating display information indicating photographing positioninformation of photographed image data, it is unnecessary to executeprocessing for associating the display information with a GPS log, it ispossible to directly acquire the display information from attributeinformation corresponding to the image data, and it is possible toperform efficient display information generation processing with lightloads.

Moreover, according to another embodiment of the invention, frequency ofphotographing is monitored to calculate frequency of use per unit timeand, when the frequency of use is lower than a predetermined threshold,intermittent power supply to the GPS device is executed. Thus, wastefulpower consumption in the GPS device is prevented and consumption of abattery is controlled. Intermittent driving of the GPS device makes itpossible to maintain a navigation message, which is reception data froma GPS satellite, in a navigation message having an unexpired term ofvalidity and perform position calculation in a short time using thenavigation message without performing new GPS satellite search.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations, and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

1. An imaging apparatus, comprising: an imaging unit configured toexecute processing to capture an image; a GPS (Global PositioningSystem) device configured to execute position calculation processingbased on data received from a satellite; a power-supply control unitconfigured to control power supply to the GPS device; an apparatuscontrol unit configured to monitor a state of photographing by a user tocalculate a frequency of use of the imaging unit per unit time, and tocause the power-supply control unit to intermittently supply power tothe GPS device when the calculated use frequency is lower than apredetermined threshold; and a data-recording control unit configured togenerate photographed data attribute information in which positionalinformation acquired in the GPS device is set as attribute informationof an acquired image in the imaging unit, and to execute processing tostore the photographed data attribute information in a storing unit. 2.An imaging apparatus according to claim 1, wherein the data-recordingcontrol unit is configured to execute processing to record latitude andlongitude information and time information acquired in the GPS device inthe storing unit as the photographed data attribute information.
 3. Animaging apparatus according to claim 1, further comprising adata-display control unit configured to read the photographed dataattribute information stored in the storing unit and to generate displayinformation indicating a photographing position on a map based onpositional information corresponding to image data included in thephotographed data attribute information.
 4. An imaging apparatusaccording to claim 3, wherein the data-display control unit isconfigured to generate display information indicating a moving locus ofthe user based on photographing time information corresponding to theimage data included in the photographed data attribute information. 5.An imaging apparatus according to claim 3, wherein the data-displaycontrol unit is configured to read plural pieces of photographed dataattribute information corresponding to plural different photographedimage data files, to merge the plural pieces of photographed dataattribute information, and to generate display information in whichphotographing positions of images included in the plural differentphotographed image data files are displayed on a map.
 6. An imagingapparatus according to claim 1, wherein the apparatus control unit isconfigured to calculate a photographing frequency in the imagingapparatus and to cause the power-supply control unit to intermittentlysupply power to the GPS device when the calculated photographingfrequency is lower than a preset threshold, and to cause thepower-supply control unit to supply continuous power to the GPS devicewhen the calculated photographing frequency is equal to or greater thanthe preset threshold.
 7. A data recording method in an imagingapparatus, the method comprising: capturing an image; monitoring a stateof photographing by a user to calculate a frequency of use of theimaging apparatus per unit time; controlling power supplied to a GPS(Global Positioning System) device configured to execute positioncalculation processing based on data received from a satellite so thatpower is intermittently supplied to the GPS device when the calculateduse frequency is lower than a predetermined threshold; performingpositioning by the GPS device; and generating photographed dataattribute information in which positional information acquired in theGPS device is set as attribute information of the captured image andstoring the photographed data attribute information in a storing unit.8. A data recording method according to claim 7, wherein the generatingand storing steps include recording latitude and longitude informationand time information acquired in the GPS device in the storing unit asthe photographed data attribute information.
 9. A data-display controlmethod for image data in an imaging apparatus, the method comprising:reading photographed data attribute information stored in a storing unitand acquiring positional information corresponding to image dataincluded in the photographed data attribute information; acquiring mapinformation of a position corresponding to the positional informationfrom a map database based on positional information corresponding to theimage data; and generating display information in which identificationinformation indicating the position corresponding to the image data isset on a map acquired from the map database and outputting the displayinformation to a display unit.
 10. A data-display control methodaccording to claim 9, further comprising generating display informationindicating a moving locus of a user based on photographing timeinformation corresponding to the image data included in the photographeddata attribute information.
 11. A data-display control method accordingto claim 9, further comprising reading plural pieces of photographeddata attribute information corresponding to plural differentphotographed image data files, merging the plural pieces of photographeddata attribute information, and generating display information in whichphotographing positions of images included in the plural differentphotographed image data files are displayed on a map.
 12. A computerprogram that causes a computer to execute a data recording method in animaging apparatus, the method comprising: capturing an image; monitoringa state of photographing by a user to calculate a frequency of use ofthe imaging apparatus per unit time; controlling power supplied to a GPS(Global Positioning System) device configured to execute positioncalculation processing based on data received from a satellite so thatpower is intermittently supplied to the GPS device when the calculateduse frequency is lower than a predetermined threshold; performingpositioning by the GPS device; and generating photographed dataattribute information in which positional information acquired in theGPS device is set as attribute information of the captured image andstoring the photographed data attribute information in a storing unit.13. A computer program that causes a computer to execute a data-displaycontrol method for image data in an imaging apparatus, the methodcomprising: reading photographed data attribute information stored in astoring unit and acquiring positional information corresponding to imagedata included in the photographed data attribute information; acquiringmap information of a position corresponding to the positionalinformation from a map database based on positional informationcorresponding to the image data; and generating display information inwhich identification information indicating the position correspondingto the image data is set on a map acquired from the map database andoutputting the display information to a display unit.